from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select
from pydantic import BaseModel
from app.core.database import get_db
from app.core.deps import get_current_user
from app.models.report import ReportTemplate, ReportTask
from app.models.user import User

router = APIRouter(prefix="/reports", tags=["报表管理"])


class TemplateCreate(BaseModel):
    name: str
    report_type: str
    description: str | None = None
    fields: list[dict]
    filters: dict | None = None
    aggregation: str = "sum"
    time_granularity: str = "hour"


class TaskCreate(BaseModel):
    template_id: int
    name: str | None = None
    schedule: str | None = None
    recipients: list[str] | None = None
    export_format: str = "xlsx"


@router.get("/templates")
async def list_templates(db: AsyncSession = Depends(get_db), user: User = Depends(get_current_user)):
    result = await db.execute(select(ReportTemplate).order_by(ReportTemplate.id))
    return [{
        "id": t.id, "name": t.name, "report_type": t.report_type, "description": t.description,
        "fields": t.fields, "is_system": t.is_system, "aggregation": t.aggregation,
        "time_granularity": t.time_granularity,
    } for t in result.scalars().all()]


@router.post("/templates")
async def create_template(data: TemplateCreate, db: AsyncSession = Depends(get_db), user: User = Depends(get_current_user)):
    template = ReportTemplate(**data.model_dump(), created_by=user.id)
    db.add(template)
    await db.flush()
    return {"id": template.id, "name": template.name}


@router.get("/tasks")
async def list_tasks(db: AsyncSession = Depends(get_db), user: User = Depends(get_current_user)):
    result = await db.execute(select(ReportTask).order_by(ReportTask.id.desc()))
    return [{
        "id": t.id, "template_id": t.template_id, "name": t.name, "schedule": t.schedule,
        "status": t.status, "export_format": t.export_format, "file_path": t.file_path,
        "last_run": str(t.last_run) if t.last_run else None,
    } for t in result.scalars().all()]


@router.post("/tasks")
async def create_task(data: TaskCreate, db: AsyncSession = Depends(get_db), user: User = Depends(get_current_user)):
    task = ReportTask(**data.model_dump(), created_by=user.id)
    db.add(task)
    await db.flush()
    return {"id": task.id}


@router.post("/tasks/{task_id}/run")
async def run_task(task_id: int, db: AsyncSession = Depends(get_db), user: User = Depends(get_current_user)):
    result = await db.execute(select(ReportTask).where(ReportTask.id == task_id))
    task = result.scalar_one_or_none()
    if not task:
        raise HTTPException(status_code=404, detail="任务不存在")
    task.status = "running"
    # TODO: trigger Celery task
    return {"message": "报表生成中", "task_id": task.id}